Keep in mind that all these results are temporary and subject to more calibration.
So we can run the model as a single species “snapper” complex. What we get, basically, is that no real improvement is possible for biomass without blocking also the small boats (5-15GT).
Look at the landings for each fleet (small, medium, large) when we block only large longliners from going out (darker color are simulations with more stringent effort control; darkest is 50 days out at max):
compared to when we block everybody: